1. Field of the Invention
This invention relates to a method for making a shoe, more particularly to a method for making a shoe having a midsole formed in a recess in an outsole and an insole that encloses the midsole.
2. Description of the Related Art
FIG. 1 illustrates a conventional method for forming a midsole between an upper and an outsole of a shoe in a mold 4. Formation of the shoe is performed on a rotary type injection molding machine (not shown) which includes an injection device and a rotatable disc with a plurality of identical molds thereon for mass production. In operation, the disc continuously rotates in such a manner that each mold is injected with a molding material via the injection device when the mold is turned to an injecting position of the injection device, and is continuously turned along with the disc to permit the injected molding material to undergo curing and cooling processes. The thus formed shoe is then removed from the mold when the latter runs through a cycle.
The aforesaid method is disadvantageous in that since a bottom 101 of the outsole 1 is patterned and is relatively thin, an inner wall 403 of a bottom mold part 401 of the mold 4 is required to have a pattern which conforms to that of the bottom 101 of the outsole 1 so as to prevent undesired deformation of the outsole 1 during the molding process, and since the bottom mold part 401 is a part of the mold 4, which requires a high precision to match with other mold parts of the mold 4, the manufacturing cost thereof is costly. As such, it is relatively costly to prepare different molds for making different shoes that differ in the pattern of the outsole. Moreover, since a portion of the midsole 5 is exposed to the atmosphere, when a filler, such as plastic waste in the form of pellets, is to be added in the midsole 5, some of the pellets may protrude outwardly from said portion of the midsole 5, thereby adversely affecting the appearance of the shoe. When a foamable material is used as the molding material, the curing time is longer as the dimension of the midsole 5 is larger, which increases the aforesaid cycle of the mold on the machine and slows down the production rate of the shoe. Since the machine is relatively expansive, higher costs are incurred when the production rate is slow. Furthermore, the midsole 5 is required to have a high density and a closed cell structure for preventing penetration of water from an outer surface of the exposed portion of the midsole 5.
Therefore, the object of the present invention is to provide a method for making a shoe that is capable of overcoming the aforementioned drawbacks.
According to the present invention, a method for making a shoe comprises the steps of: preparing an outsole having a bottom wall and a peripheral side wall extending from the bottom wall in a transverse direction relative to the bottom wall and cooperating with the bottom wall to confine a recess therebetween; placing the outsole in a first mold; filling and molding a first molding material in the recess in the outsole in the first mold so as to form a midsole in the recess; preparing an upper having a bottom; preparing a second mold that has an upper mold part with a last, a bottom mold part opposite to the last, and a side mold part that cooperates with the last and the bottom mold part to confine a mold cavity thereamong; placing an assembly of the midsole, the outsole, and the upper in the mold cavity such that the bottom wall of the outsole is pressed against an inner wall of the bottom mold part, that the upper is fittingly sleeved on the last, and that the upper, the outsole, and the midsole cooperately confine an inner cavity thereamong; and filling and molding a second molding material in the inner cavity so as to form an insole that is bonded to the bottom of the upper, the peripheral side wall of the outsole, and the midsole.